Plastic tank base

ABSTRACT

An improved pallet and tank assembly ( 10 ) is provided, including a metal tank ( 12 ) positioned atop and secured to a flat-bottomed, synthetic resin pallet ( 14 ). Preferably, the pallet ( 14 ) includes an upper tank-supporting slotted surface ( 40 ) which receives depending couplers ( 28 ) serving to secure the tank ( 12 ) to the pallet ( 14 ) and allowing field-replacement of the pallet ( 14 ) without the need for welding or the like. The pallet ( 14 ) presents a substantially flat bottom ( 44 ) having a plurality of enlarged foot structures ( 60 ) and interconnecting rails ( 62 ) serving to evenly distribute loaded weights.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention is broadly concerned with improved tank and pallet assemblies preferably having an all-metal hazardous material tank positioned atop and secured to an underlying, flat-bottomed synthetic pallet. More particularly, it is concerned with such assemblies wherein the pallet permits four-way tongue lifting, is capable of being carried by a variety of conveyors, and gives substantial vibration-dampening and tank load-spreading.

2. Description of the Prior Art

Metal tanks are the preferred and most common method of storing and transporting hazardous and flammable material. The current form of metal tanks consists of an all-metal tank vessel supported by four or more legs typically mounted at the corners of the tank bottom. Tanks of this type commonly have a valve located on one of the tank sides with a protective barrier directly behind the valve. This limits the user to only three-way forklift entry. Although the tank legs allow for stacking and forklift/pallet jack access to the tank, the leg structures and methods of attachment to the tank have many limitations. For example, current tanks having corner legs cannot pass over roller or ball conveyors. Further, the current leg designs and locations concentrate load forces on a small section of the tank body, limiting the load-bearing capacity of the legs and rendering them more prone to failure. Finally, all-metal tanks with corner legs cannot be fitted with Radio Frequency Identification (RFID) Tags which are critical for effective tracking of containers carrying hazardous or toxic materials.

U.S. Pat. No. 5,316,174 describes a pallet container designed for supporting a tank having an inner synthetic resin container with an outer metallic wall. The tank is designed to rest atop the pallet, with no mechanical interconnection between the tank and pallet. The pallet of the '174 patent is also not designed for four-way lift tongue usage.

SUMMARY OF THE INVENTION

The present invention overcomes the problems outlined above and provides a tank and pallet assembly comprising a tank presenting a base, upright, circumferentially extending sidewall structure, a top wall, and a plurality of depending connectors extending from the base. A pallet is also provided having a top wall-with an upper surface matingly receiving and engaging the tank base, with the pallet having at least one opening through the top surface and receiving corresponding connectors; the pallet also presents a substantially flat bottom surface. Fasteners are used to operably couple the tank-mounted connectors to the pallet to present an integrated tank/pallet assembly.

In preferred forms, the tank is formed of metal such as stainless steel, while the pallet is formed of synthetic resin material. The tank is preferably quadrate in plan configuration, having a substantially flat base equipped with a drain valve, and a top wall having a fill port. The fasteners are downwardly extending, apertured connector plates.

The preferred pallet is also preferably quadrate in plan configuration and has a slotted upper surface receiving the tank-mounted connectors. Pin assemblies are used to interconnect the tank and pallet. In one preferred embodiment, the connectors are in the form of aligned, generally U-shaped elements, and at least one elongated connector rod extends through the confines of each of the elements, in order to secure the tank to the pallet. Advantageously, the pallet is designed to permit four-way entrance of lifting tongues.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of a tank and pallet assembly in accordance with the invention;

FIG. 2 is a perspective exploded view of the FIG. 1 assembly, depicting the upper surface of the pallet;

FIG. 3 is a perspective exploded view of the FIG. 1 assembly, illustrating the lower surfaces of the pallet and tank;

FIG. 4 is a fragmentary vertical sectional view illustrating the placement of the tank on the pallet with the tank drain valve received within the pallet recess;

FIG. 5 is a fragmentary vertical sectional view illustrating the interconnection of the tank to the pallet, using the tank-mounted connectors received within pallet slots and coupled together via a cross-pin assembly;

FIG. 6 is a fragmentary perspective view illustrating a metal tank and synthetic resin pallet combination having preferred connection structure securing the tank to the pallet;

FIG. 7 is a fragmentary, perspective exploded view depicting the combination of FIG. 6, and illustrating the underside of the tank and aspects of the preferred connection structure;

FIG. 8 is a fragmentary, perspective exploded view of the combination of FIG. 6, and illustrating the upper surface of the pallet;

FIG. 9 is a vertical sectional view taken along line 9-9 of FIG. 6; and

FIG. 10 is a vertical sectional view taken along line 10-10 of FIG. 9.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

Turning now to the drawings, a tank and pallet assembly 10 is depicted in FIGS. 1-3, and broadly includes an upright tank 12 situated atop a specially designed pallet 14. In preferred forms, the tank 12 is formed of metal (e.g., stainless steel), whereas the pallet 14 is fabricated from an appropriate synthetic resin material using molding techniques (e.g., injection, blow, compression, or rotation molding). The assembly 10 eliminates the problems of tank legs and allows transport on conveyors and the like.

In more detail, the tank 12 includes a generally flat base 16 as well as upstanding, circumferential sidewall structure 18 and a top wall 20. As best seen in FIG. 3, the base 16 is equipped with a drain valve 22 as well as four mated pairs 24 a, 24 b, 24 c, and 24 d of connector tabs 26. Each tab 26 extends downwardly from the base 16 and has an aperture 28 formed therein. The base 16 has a rounded periphery 30 which merges into the upstanding sidewall structure 18. The latter also has rounded upright corners 32. The top wall 20 includes a selectively openable fill port 34 allowing the tank 12 to be filled with liquid. In addition, corner brackets 36 are secured to the tank 12 at the juncture between sidewall structure 18 and top wall 20. As shown, the sidewall structure 18 has a rounded upper periphery 38 merging into top wall 20.

The pallet 14 broadly includes a top wall presenting an upper surface 40, depending, circumferential sidewall structure 42 and a substantially flat bottom surface 44. The sidewall structure 42 presents a rear wall 44 a, lateral walls 44 b, and front wall 44 c. As best illustrated in FIG. 3, the pallet 14 has a series of intersecting, substantially orthogonal strengthening walls 46 beneath surface 40 and defining individual, vertically extending, open-bottom cells 48.

The top surface 40 is equipped with an upstanding short lip 41 sized to engage base 16 of tank 12. Additionally, a series of openings are provided which extend through the top wall and upper surface and which are not interrupted by cell walls 46. Specifically, the pallet 14 has a pair of rearmost, laterally spaced apart, aligned slots 50 adjacent rear wall 44 a, together with four side slots 52 adjacent the lateral walls 44 b and arranged in fore and aft, aligned relationship. Additionally, a pair of laterally spaced apart and aligned slots 54 are provided in the central region of surface 40. The front wall 44 c has a recess 56 formed therein, which is sized to receive drain valve 22.

Each of the walls 44 a, 44 b, and 44 c has a pair of spaced apart slots 58 formed therein, which are below the bottom surfaces of the walls 46 and thus afford openings for insertion of lift tongues (not shown). It will be observed that these slots 58 allow lift tongues to be inserted from all of the walls 44 a-44 c.

The bottom 44 of the pallet 14 presents a series of enlarged, cellular foot structures 60 located at each corner of the pallet, centrally along the walls 44 a, 44 b, and 44 c between the corners, and at the geometrical center of the pallet. The bottom surfaces of the foot structure 60 are substantially coplanar so that the overall surface is flat. Additionally, ribbed bottom rails 62 extend between the corner and intermediate foot structures 60 and between the central foot structure and the intermediate foot structures, to provide additional support. It will be seen that the previously described tongue slots 58 are provided between the rails 62 and the top surface 40.

In use, the tank 12 is placed atop pallet 14, with the connectors 26 received within corresponding pallet slots and in bridging relationship to adjacent foot structures. Specifically, the central pair 24 a of connectors 26 is received within the central slots 54 and bridge the central foot structure 60; the rearmost pair 24 d is received within the slots 50 and bridges the intermediate foot structure 60 along wall 44 a; and the side pairs 24 b and 24 c are received within the slots 52 and bridge the intermediate foot structures 60 along walls 44 b. The connectors 26 are of a length to extend downwardly through the associated slots in closely fitting relationship with the associated foot structure. In order to complete the connection between tank 12 and pallet 14, fastening assemblies 64 are used. Each assembly 64 includes a pin 66, washer 68, and clip 70. Specifically, each pin 66 is passed through the openings 28 provided in the connectors 26, and through aligned, pre-drilled openings 72 extending through the foot structures 60. The washers 68 and clip 70 are then used to complete the connection.

FIGS. 6-10 illustrate another tank and pallet assembly 10 a including a metallic upright tank 12 a and supporting synthetic resin pallet 14 a. In many respects, the tank 12 a and 14 a are similar or identical with previously described tank 12 and pallet 14, and accordingly like reference numerals are used between these embodiments and only the differences are specifically described.

Thus, the tank 12 a has flat base 16, upstanding, circumferential sidewall structure 18, and a top (not shown). The base 16 is equipped with a drain valve 22 as best seen in FIGS. 6 and 7. The underside of base 16 includes a series of three aligned, depending, generally U-shaped connectors 74 in lieu of the connector tabs 26. In all other respects, the tank 12 a is identical with tank 12.

The pallet 14 a has a top wall presenting an upper surface 40, depending, circumferential sidewall structure 42, and a substantially flat bottom surface 44. Top surface 40 is equipped with lip 41 sized to engage base 16 of tank 12 a and also has a series of openings including side slots 52. Intersecting, substantially orthogonal strengthening walls 46 are provided beneath surface 40 and define individual, vertically-extending open-bottom cells 48. The top wall 40 also has three aligned connector-receiving slots 76 each defined by a pair of lateral sidewalls 78, end walls 80, and a bottom wall 82. The slots 76 are configured to receive the connectors 74 as described below. Referring to FIGS. 8-10, the base of pallet 14 a also has a pair of aligned openings 84 which extend laterally through the lateral walls 44 b and through the side walls 78 of the slots 76. A pair of elongated connecting rods 86 extend fully through the openings 84 and through the confines of the individual connectors 78 (see FIG. 10). One end of each of the rods 86 is equipped with an apertured attachment tab 88, and threaded fasteners 90 are used to secure the rods 86 in their locking positions.

The sidewall structure 42 includes rear wall 44 a, lateral walls 44 b, and front wall 44 c. Each of the walls 44 a, 44 b, and 44 c has a pair of spaced apart slots 58 formed therein, which are below the bottom surfaces of the walls 46, affording openings for insertion of lift tongues (not shown). The underside of pallet 14 a is configured identically with that of pallet 14, and thus needs no further description.

In use, the tank 12 a is placed atop pallet 14 a, with the connectors 74 received within corresponding slots 76. Next, the rods 86 are passed through the openings 84 and the fasteners 90 are used to secure the rods in place as best depicted in FIG. 9. This serves to firmly secure the tank 12 a to pallet 14 a.

The assemblies 10 and 10 a provide a number of advantages over existing tank and pallet designs. The pallets 14, 14 a being of synethetic resin construction, provide vibration dampening for the tanks 12, 12 a, which prolongs tank life and reduces the risk of failure. The pallets 14, 14 a also increase the load rating of the associated tanks by distributing the loaded weight over a greater surface area. The assemblies of the invention can all be used on all types of conveyors including roller and ball conveyors. The assemblies can also accommodate RFID tag mounting, something heretofore not possible with all-metal designs. The pallets 14, 14 a also afford four-way forklift or pallet jack entry, and may be field-replaced without the need for welding. 

1. A tank and pallet assembly comprising: a tank presenting a base, upright, circumferentially extending sidewall structure, a top wall, and at least one depending connector extending from said base; a pallet having a top surface matingly receiving and engaging said tank base, said pallet having at least one opening through said top surface and receiving said at least one connector, said pallet presenting a substantially flat bottom surface; and a fastener operably coupling said at least one connector to said pallet.
 2. The assembly of claim 1, said tank having a drain adjacent said base, said pallet having a recess receiving said drain.
 3. The assembly of claim 1, said tank formed of metal, said pallet formed of synthetic resin material.
 4. The assembly of claim 1, said pallet having upstanding peripheral wall structure engaging portions of said tank.
 5. The assembly of claim 1, said tank top wall having a fill port.
 6. The assembly of claim 1, said at least one connector further comprising a plurality of mated pairs of elongated, apertured connection tabs.
 7. The assembly of claim 6, further comprising a plurality of openings comprising slots receiving said mated tab pairs.
 8. The assembly of claim 7, further including a plurality of fasteners comprising a pin fastener extending through the apertures of mated tab pairs.
 9. The assembly of claim 1, said pallet having recesses formed between the top and bottom surfaces thereof permitting insertion of lift tongues therein.
 10. The assembly of claim 1, said pallet and tank being substantially quadrate in plan configuration.
 11. The assembly of claim 1, said pallet having a series of generally orthogonal strengthening walls below said top surface and defining a series of cells.
 12. The assembly of claim 1, said pallet having supporting foot structures at the corners thereof, with intermediate supporting foot structure between the corner foot structures.
 13. The assembly of claim 12, including bottom surfaces extending between said foot structures.
 14. The assembly of claim 1, said pallet being substantially quadrate in plan configuration, and having a pair of lift tongue-receiving recesses along each side thereof, such that the pallet and tank may be elevated using lift tongues inserted at any one of the four sides thereof.
 15. The assembly of claim 1, there being four mated pairs of said fasteners, each mated pair being received within a corresponding pair of said pallet openings.
 16. The assembly of claim 1, said at least one connector comprising a plurality of generally U-shaped elements.
 17. The assembly of claim 16, said fastener comprising at least one elongated connecting rod extending through said elements.
 18. The assembly of claim 17, including a pair of connecting rods extending through each of said elements. 